Titanium tool steel



March 25, 1958 c. G. GOETZEL ET AL 2,828,202

TITANIUM TOOL STEEL 2 Sheets-Sheet Filed Oct. 8, 1954 March 25, v 1958 Filed Oct 8, 1954 C. G. GOETZEL ETAL- TITANIUM TOOL STEEL 2 Sheets-Sheet arrmw-y United States Patent IOOUSTEEL iClausv G. :Goetzel, Yonkers, :N. Y., NicholasJ. Grant, :Winchester, .Mass., .and'Leonard P. Skolniclr, T'New "York, and John'L'Ellis; White PlainsgNiY a's'signors to. Sintercast (Zorporafion of =-America, Yo'nkersfN; -Y.

:Application ctober,8,l954,"Serial No. 461 143 14 Claims. {(Cl 75- 123) tste'els. ITitaniumcombined withscarboniisvfil'y hafdgis JV (substantially resistant to wear-and galling issubstantially resistant to corrosion, has a. lowrcoefiicienti ,io'f ffiicftion, .has .a. relatively high heat conductivitynand also; has airlalively: low specific {gravity compared. .to other carbides,

such as tungsten carbide molybdenum ca'r bide,tetc. fllIn laddition, titanium, unlike tungsten; ..is non strategic ,is ..available domestically ,in very,la1;ge'. quantities. and; snot aafiected 'byynational emergencies arising from unstable worldmsituations. Yet, with all these,attradtivejlfeatures in" its 'favor,;itl has not been possibleLto utilize ,t'itanium A in large amounts commercially" inr'the: production of gsteels in .thetsense .that tungsten andmheavy refractory metals 'are. employed in the. production ofthighi speed, and

,toolsteels. 'TThe additionrof titanium .to (amolte trous metal in amounts .exceedingjaboutf51%1 has Lbeen known to have such an embrittling. fiect ,vongfth stilt lingjferrous alloys as totma'ke t the, alloy, unworka lel and .tunsuitablefor-the commercial (production, of aUSfill; prenuctsr ."Particular care must be' taken;inusing'titaiiiumias an alloying ingredient in view of its highmpropensityf to react chemically with oxygen .andnitrogen, whichjle ments, when combined with titanium,are known'td" have deleterious effects on the properties gofthe alloy.

When titanium is added to ta molten bath o'fagcarbon containing'ferrous metal'by conventional meltingprocedures, titanium carbide or artitaniumicompoun d based on carbon is formed, generally as large dendritic aggregates during solidification. Because ofthe relativelylow specific gravity of the carbide, it'has a tendency to; form large undesirable aggregates which make it diificultto obtaina uniform product having a .controlled carbide size and uniformlcarbide distribution. "These aggregates 55 and segregates oftenform 'an undesirable continuous phase which cannot bebroken up into discretea'small particles'by Working,-, and therefore impart extremeib'rittleness to the alloy. The aforementionedIdisadvantages t which accruerfrom using titanium as an alloyingingre-- "dient .in steels have militatedagainst its-use in ithejproauction of hard tough alloys, particularly'initheprdduction of high titanium, high"'carbon'toolsteels. ..Furthermore, the usefulness of "such types "of steel "was not i'knownowing to the fact that theywere not'available.

Aspecial high titanium, high carbon ferrous"a1loy has now" been discovered containing substantial amounts of titanium, i. -e.,-at least about by"weight,'saidalloy being characterized by substantialfreedom from unde- 'sirab1e large dendritic aggregates and segregates -"'of titani-um carbide and also characterized by high hardness "combined with high heat and corrosion resistance, "Strength andresistance'to wearand abrasion.

2,828,262 Patented Mar. 25, 1958 "ice ThegexpressionTferrous alloy ,as employed-herein is meant to include an alloy containingatfleast.about,10%

titanium by "weight substantially as titanium carbides uniyforrnly distributed through .aiferroustmat'rix which-may 5 comprise carbon steel, tmediumflalloyr steel orghigh alloy j'steel. The titanium containingfferrous alloy; has theiheat L?treatable char Qteristics oftsteel. 7

,It isja'n object of 1the, ,p re sent invent ion togprovide a ';;heat treatablefferrous alloy containingghigh amounts-.of .ititanium and, carbon, yet characterized-by. a. substantially g non continuous carbide phase. a

.IjAno'ther object, of the invention-T is tor-Provide a, asjngot 'orbar stock an annealable tool steel-type composition v fcontaininghigh amountsfof .tit-ahium and carbon "and .j capable of being machined to various shapes in .sub-

'stantia'llv'the annealed condition.

T A.. further object of the invention is to provide=a 'fer- 'rous alloy rich in titanium an'd carbonqan'd, capablesof being hardened to har'driesses of an order of magnitude comparable to cemented: tungsten carbides.

.. qtflther ohjects and advantages "will -sbecome apparent iironn'the'jfollowing description.takentin conjunction with 'the'accomp'anying drawingin which: 3

Fig. 1 is a reproduction of a photograph :showingbar stock of the titanium and 'earbon-ifih fer'rous alloy' being machined in the conventional-manner with a cutting'toolg Fig. 2 depicts a reproduction of a photomicrograiph taken at 1000 diameters 'showi-ngsan annealed; structure of the ferrous alloy provided by the-invention;

Fig. 3 shows a reproduction-(at a photomicrograph taken at 1000 diameters illustrating a variation 'of an 'annealed structure of the .ferrousaalloy;

Fig. 4 is a reproduction of aphotornicrograph taken f at 1060' diameters showing the hardened structure of. the

' '3 -ferrous=al=loy prot' ided -by the invention;

Fig. 5 is a reproduction of a photomicrograph taken at 1000 diameters showingg-anothe eharidenedastructure-gof the ferrous alloy providedby thei vention;-=an'd Fig. 6 is a diagram comparinggthemecoveryhardnesses 40 of two ferrous alloysof theyinvention ywithithe; recovery hardness (of a prior artsteel.

".Broadlyl 'stated, the present: inventionfgproyides aihigh ftitanium; jhigh"carbon ferrous alloyi'havingjthe heatitreatability of commerciaFhighjalIoy tool steels, suchgas, high 5 sped steelsfand atfthesar nefltime having some (of the idesira-blei attributes of 'cementedjtungsten carbides. The t'ferrous "alloy 'contains"titanium and carbon 'as essenftial ingredients in amounts]-substantially in 'excess io'f Zthose "usually -considered"detrimental in steel. By ntilizjng these twojelements in a cooperative" manner, a'heatf treatable gandguseful ferrous: 'alloy product can "be prdducedjcontainingatdea'st about 10% and generally upv to about 70%byweight of titaniumyprovided "the .t'itaniumis ypreseuth the alloy in a specialform.

The'prdductlof the invention'is achieved by employing "titaniurn and carbontogether ima combined form comprising substantiallytitanium'carbide as an alloyingim gredient with a steel which cooperates with the titanium carbide'inproducingthe desired results. "The-steel em- ,ployed inithe'invention contains ironasfthe major alloy- 'ing element' which generally comprises at least "about 60% by; Weight of the-"steel. Thus, "-in'c I TS in'g '0ut'the invention,'-"the steel may be an alloy"'steel;a'carborr'steel -or -maycomprise pure iron which in practicing the inventionyWill combine with carbon to form a steel. When the-"steel 'is-employed in 2 forming the high"titanium, high "carboniferrous alloy containingabout l0% to %,-and --pr'ferablyabout 20% to 58%,-by weightoftitaniumflthe *tOtaI amountof carbon in the "alloy must 'beat -least sufid- 70 -eient 'to' be-incombination with-"the titanium -as titanium ficarbi'de and also i be suflicientto confer heat -'treatability "'to the ferrous matrix. The expression fe'rrous *mat'rix as employed herein is one which crystallographically at ordinary temperatures is characterized by a substantially ferritic or body centered cubic structure and which at an elevated temperature below the melting point of the ferrous alloy is transformed to a substantially austenitic or face centered cubic structure.

The ferrous alloy product of the invention containing. the aforementloned amounts of titanium over the broad in place of metallic titanium, massive carbide dendrites and continuous segregates are avoided and a useful product is obtained.

The following examples are indicative of useful compositions provided by the invention.

Example I An alloy useful for single point cutting tools and other similar applications requiring high hardness has the following composition:

About 65% by weight titanium About 10.9% by weight iron About 2% by weight cobalt About 0.7% by weight chromium About 0.3% by weight vanadium About 3.0% by weight tungsten About 18.1% by weight carbon Example 2 A composition which is very useful where toughness The preferred range of proximately 670 C.

along with high resistance to wear and galling is required is as follows:

About 39% by weight titanium About 10.3% by weight carbon About 0.7% by weight chromium About 50% by weight iron Theforegoing examples illustrate that titanium in high amounts can be utilized in the ferrous alloy provided by the invention. By utilizing titanium in the form of titanium carbide, rather than metallic titanium, beneficial rather than adverse results are obtained. Tests have indicated that titanium carbide when employed in combination with a steel, for example low carbon steel, reacts with the latter due to a partial solution of the titanium carbide therein during high temperature heating involving liquid and solid phase reactions, whereby the ferrous matrix of the resulting ferrous alloy is provided with additional alloy and carbon content for improving the hardenability, resistance to tempering, hot hardness, resistance to deformation and wear, etc. ferrous matrix is derived from a high alloy steel, an improvement in the final properties of'the ferrous alloy is effected.

The partial solubility of titanium carbide in the ferrous matrix is particularly desirable as it results in microstructures which are beneficial to the properties of the alloy, particularly resistance to wear and deformation. Such microstructures may comprise well rounded or partially rounded or substantially angular grains of titanium carbide dispersed uniformly throughout the ferrous mais a reproduction of a photomicrograph taken at 1000' diameters, shows the microstructure of the ferrous alloy in the annealed condition comprising partially rounded containing substantial amounts of spheroidite.

through a pearlite ferrous matrix. Fig. 3, also taken at 1000 diameters, shows partially rounded titanium carbide grains dispersed through a similar ferrous matrix The microstructure of Fig. 4, taken at 1000 diameters, shows well rounded titanium carbide grains also dispersed through a similar ferrous matrix comprising primarily martensite resulting from a water quench treatment from a temperature of about 985 C. Figure 5 is similar to Figure 4, except that it shows angular titanium carbide grains dispersed through a martensitic ferrous matrix. This structure is advantageous in cutting tools.

Figure 6 is a diagram showing the recovery hardness of two alloys of the invention (curves A and B). By recovery hardness is meant the room temperature hardness of an alloy which had previously been hardened andpreheated to the temperatures indicated in the diagram. For comparison, a curve of the recovery hardness of a conventional 18-4-1 type high speed steel is presented (curve X). Curve A represents the recovery hardness of a ferrous alloy of the invention comprising approximately titanium, carbon sufficient to combine with the titanium, with the balance substantially iron. The recovery hardness of this alloy is superior to that represented by curve X at temperatures above ap- It is also superior in recovery hardness at temperatures below approximately 440 C. Curve B represents the recovery hardness of a ferrous alloy of the invention comprising approximately 50% titanium, 10% tungsten, 2% chromium with small amounts of vanadium and sufi'icient carbon to combine with substantially all the titanium and to confer heat treatability to the ferrous matrix. The recovery hardness of this ferrous alloy is superior to that of the conventional alloy at all temperature ranges up to about 1000 C.

It will be appreciated from the foregoing that the high titanium, high carbon ferrous alloy provided by the invention can be heat treated like conventional steels to provide hard or annealed structures. But unlike the conventional steels, certain ferrous alloys of the invention exhibit their maximum toughness in the fully hardened condition. For example, a ferrous alloy comprising about 35% by weight of titanium with the balance substantially iron and carbon combined with the titanium generally exhibits in the annealed condition an impact resistance of about 8 inch-pounds when tested in izod Even when the 1 titanium carbide grains distributed substantially uniformly on an unnotched 35 inch square specimen. However, when the same alloy is rendered fully hard by water quenching from about 985 C. the resistance to impact improves to about 13 inch-pounds. Thus, the impact resistance in the fully hardened condition is better than in the annealed condition, whereas, the reverse is true for most conventional steels.

Examples of steels which may be employed in combination with titanium carbide in producing the ferrous alloy of the invention include low, medium and high carbon steels. Such steels include SAE 1010 steel, SAE 1020 steel, SAE 1030 steel, SAE 1040 steel, SAE 1080 steel, etc. Pure iron may be used, since it combines with carbon to form a steel during the process of producing the ferrous alloy of the invention. Low, medium and high alloy steels may also be employed, including the following: about 0.8% chromium, 0.2% molybdenum, about 0.30% carbon, and iron substantially the balance; about 5% chromium, 1.4% molybdenum, 1.4% tungsten, 0.45% vanadium, 0.35% carbon, and iron substantially the balance; about 8% molybdenum, 4% chromium, 2% vanadium, 0.85% carbon, and iron substantially the balance; about 18% tungsten, 4% chromium, 1% vanadium, 0.75% carbon, and iron substantially the balance; about 20% tungsten, 12% cobalt, 4% chromium, 2% vanadium, 0.80% carbon, and iron substantially the balance; and generally other types of steels characterized crystallographically by a body centered cubic structure at ordinary temperatures and by being transformsbie to a face centered cubic structure av an-elevated temperature below i 'lhe titanium earbide employd in -the: lloymay congtain limited amounts of other carbides, preferably in solid' solution therewithgwithout departing front the scope of the invention. 'l husy the titanium carbide may be replaced in part by up toabout 35% of tungsten carbide, up to about 35% vanadium carbide, up to about 25% .z-Zirconiumzca'rbideaup 4013130111; 1 0.%;c"olumbium carbide, up to about tantalum carbide, etc., theitotahamount of these carbides not exceeding about 50% by weight of the total carbides present. *ln o'ther wvofdsthecarbide employed in the ferrous alloy may 'comprise titaniumbase carbides which include titanium carbideperse.

As has been stated --hereinbefore; "the 'ferrous "alloy' of the invention is amenable *to heat treatment. Thus, to anneal the alloy, itis"cooledslow1y=throughthe "A ....temp,erature..so .ias rto .produce...a.mierostructure .in the .iferrous;matrix..consisting;of,pearlite and spheroidite. ..By 1A .temperature..is,..meant that temperature at whichuthe =i face.centeredcubic crystalyis...transformed tola body-used .utered cubic...crystallinestructure. ..In hardening, .the.alloy is..heate.d.- to .an :austenitization temperaturessufllcientl to ...convert, .substantiallythe matrix to aiace centered. cubic -stnucture-and for-a ti-meesufiicientt to tfectsatuniform ucture -and, then.subsequeritly:guenchedaby. coolingx'in p, .oil .,or waterh-depending: upon .the. hardenability-a. of tithe ferrous. alloy, thus. decomposing ,austenite: to .martensite. LTITheaustenitemay-also ,belransformed into. bai-nite .rbyuisQt-hermally aquenching. to satbainite. formation -..-temg iperature from the .a-forementionedaeaustenitiziggeternper .ature.

. tIQnexofJhe.mainzadvantagesto be gainedutrom the..in-

' wention. -.is that-.the. annealed .high .t-itanium, vhigh. carbon vttioualzmeans. .:F.or.example, vbaristoclc .comprisiug about 1.35%; byweight .of: titanium :andtthetbalaneez substantially .tcarhonizsteelaand-carhon.combinedwiththestitanium machined easily on a lat-heyto theadesired";shape,;utilizing a msteel cutting grade of cementejdltungsten carbide; when .-.i;anneale.d. to as,low as-.-40 RockwelliC. tT-he machined 1. .barustock-rwas .thenshardenedto about 725 Roekwell-..C ;by a oil; quenching? from avtemperature-inthe order ofr about 35.70": C; ::Figure.1'.il1ustrates the;ease with.whichithe-an- :..-neale.d.-alloy of, the invention canlbe machined; by an. or-

adinary euttingttool. ,This .alloyahadra titanium content of about 35% by weight which was combined -withacan 1 hon; the balance; beinguapearlitic. matrix.

.The4 novel l ierrous-salloy. of. the. invention can: .be apro- 1 ...duced substantially ifreefrom massive carbide-dendrites uiandvsegregation preferably by. interstitially casti-ngi molten .ssteel intodheiinterstiees of a coherentmoroussstrucrure ...cornprisingasubstantiallyititanium carbide grains. ..-T;his

uxialloyg for :example"1stabiliz'ed zirconia,- with ".provisions unmade for -ithe 1 molten; steel '1 to enter. the; mold .z an'd con- :stact therporousacarbide structure. lTheillIlldiofi'tefl'flcwteryirmaterial .andithe porous. carbide :structure: supported thereinnis I then placed. into ai suitableaeasting :f Sutficientzamount:of:steel:.to:produce;the castingmszp' .tratlthemoldaopening'aandithe-twvholezibrought:ztoaa: temperature of generally up to about 100 C. abovei'ther'm'elting u poiutzrottthessteelsso that thexnioltenesteel 'iflcws' interstirrous alloyuis to.-a:large-..extent:machinableby convenasaaaoa vtially into the porous body, completely filling it and providing excess feedfor shrinkagezcavitieswipesietc. a'If-he casting im achieved in vacuum for at .a sub-atmospheric pressure g'enerally :no't :exceeding: about. 200 microns of mercury. 'After -the steel i has 1 interstitially :fi1-1e'd:-a11.-1. of

the voids in the porous titanium carbide structureg and f then allowed to" reach equilibrium with it; the" carbide is mddified by partial solution in the liquid phase, -whereby itris disrupted into discrete and-uniformlya'distributed grains. The interstitiallycast ferrous-alloybody is cooled "in vacuum, is removed from the*furnace and is fin'ally =separate'd from the refractory mold. The product is then 'annealed, esgs'by" heating in a i furnace at a temperature -sup to about 4 hours "under non-oxidizing conditions; for

example-a reducing atmosphere" comprising --*'about 93f% -'perature-6f-about 540-C. "or lower. As has been pointed out'hereinbe'fore, the -microstructure" of the annealed ferr'ous' -alloy generally comprises hard grains -oftitanium -=carbide --distributed substantially uniformly "throughsan "annealed iferrous matrix, for example a -matrix having a microstructureo'f "pearl-iteyspheroidite, or martensitic decom po'sition products. The following examples illustrate in greater detail how theforegoing-method maybe employed in producing allz ys=and products of the invention:

' A hot heading tool for severe impact applications had the following alloy composition:

About 43% by weight titanium About 45.3 by weight iron About 11% by weight carbon 7 7 About 0.4% by weight'chromium About 0.2% byweight manganese About 0.1% by weight molybdenum "T he tool wasjmanufacturedmythe following technique A batchOftitaImmcarhi'de with fthe"follo'wingianal- 'was -3L78%iand the-totalcarbon20'.5l%. The-agglom- "erated-heat treatedjca'ke. wasithen crushed to "minus; 140

"mesh. AboutZOOO gramsofithis crushed "product'was placed in a one gallon stainless iste'el ni'illwhieh"was charged'with l1;500'.grams of' /zimsteel'ballsarid then 7 -halffilled withtrichlorethylene. The product'was milled for 100 hours, carefully dried and screenedthrough' 2 140 "meshsieve.

A 2 /2' inch diameter; porous cylindrical briquettegl fli "inchjhigh, 'was'then pressed at 4 tons per square inch.

it wasplacedona graphite carrier 'and-firediat about 1250" Cffor /2 hour in .a'vacuumyofilessithan I100 microns'mercury column: .JTheQfired; porous briquette "comprisedapproximately 65% by volume of titanium carbide; It wasthenplacedintoarefractory'mold' consistingof granular stabilized zirconia. Azpredetermined quantity; of metal calculatedto"completely'fill all interstic es' between the carbide'grains contained: in. the mold -plus-=a'-liberal quantity in the order of 50% excess'was 3 placed above the-mold. This excess was-necessary to "fill the mold completely 'to allow feeding of shrinkage "cavities as in conventional foundry practices. The "metal 1 inthis case consisted of molybdenum=chrome=steelSAE #4130. The charge waspla'ced-in'avacuumcasting furnace-an'd heated --'s1owly to *a temperature "of about .I'530 "C. "Melting of the-steel occurredat a pressrire of approximatelyZOO microns of 'mercury columrvat a temperature of approximately 1480 C. The molten metal was cast interstitially 'into the porous. carbide struc- -tu-re. *Thetemperature was "maintained at about F 1530" iCjfor 'one" hour so asto permit high 'fluidityiof the metal so that all voids would be completely filled and solubility and rounding of the carbide grains could occur. The melt was then allowed to cool under vacuum, then removed from the furnace, and thecasting stripped from the mold.

The rough casting was then annealed by placing it in a furnace at about 870 C. in a protective atmosphere consisting of about 93% nitrogen and about 7% hydrogen. The annealing period was 2 hours, followed by a controlled cooling at a rate of less than 15 C. per hour down to a temperature of about 540 C. The annealed structure then had a hardness of approximately 45 Rockwell C. The casting could then be turned on a lathe to the desired shape, utilizing a steel cutting grade of tungsten carbide. Usual tolerances for grinding after hardening were permitted. The machined slug was hardened by austenitizing at about 980 C. and quenched into an oil bath. The slug was then tempered for 1 hour at about 205 C. The hardened structure had a hardness of approximately 70 to 71 R Its modulus of rupture was approximately 300,000 pounds per square inch in transverse rupture and its impact strength 12 inch-pounds on an unnotched inch square specimen tested in Izod. It was then ground to finish size, cased in an alloy steel holder and was ready for use.

Example 4 A useful alloy for cutting purposes had the following composition:

About 61% by weight titanium About 18% by weight iron About 15.5% by weight carbon About 4.3% by weight tungsten About 0.9% by weight chromium About 0.2% by weight vanadium It was produced as follows:

The titanium carbide product, as treated in Example 3, was briquetted into a rectangular slab at a pressure of 10 tons per square inch. The slab was now out with a rubber bonded wheel into small rectangles inch x inch x inch, a useful size for a single point cutting tool. Similar rectangles of smaller size were briquetted directly with an automatic pill press. The bodie were fired at about 1350" C. in a vacuum of less than 100 microns of mercury column. The fired porous structures comprised approximately 85% by volume of titanium carbide. The fired bodies were placed in an open mold of beryllia, with an allotment of metal on the top of each of the porous structures. The alloy in this case consisted of an 184-1 type high-speed steel and the quantity allotted was 50% in excess of that required to fill the void volume of the porous structure. The excess was necessary for reasons explained in Example 3. The interstitial casting was conducted in vacuum at a pressure of less than 200 microns of mercury column and a temperature of about 1490 C. The castings were allowed to soak at this temperature for 40 minutes. After cooling and removal from the vacuum furnace, there was no adherence of the cast bits to the supporting ceramic mold, and the shape and size were close to that of the original porous body. The bits were hardened by quenching in oil or air from about 1040 C. and were finish ground as tool tips. The hardness was approximately 74 Rockwell C: the modulus of rupture was 230,000 pounds per square inch; and the impact on a A inch square Izod specimen was inch-pounds.

While it is preferred to produce the alloy of the invention by means of interstitial casting, it will be appreciated that other methods can be employed. For example, the titanium carbide grains may be mixed with the steel in particulate form and briquetted into the desired shape and this shape then fired at an elevated temperature, generally not exceeding about 100 C. above the melting point of the steel phase. By heating the car= bide in the presence of the liquid phase, the cooperative effects of the two constituents are achieved, whereby a heat treatable ferrous alloy is obtained.

The foregoing procedure for producing alloys of the invention is detailed in the following example:

Example 5 An alloy useful for extrusion dies had the following composition:

In producing this composition, 3700 grams of titanium carbide, as treated in Example 3, was mixed thoroughly with 6,300 grams of a tool steel in a form all passing through 325 mesh, by milling in a stainless steel mill. The product was then briquetted at a pressure of tons per square inch. This briquette was then fired in vacuum at a pressure of less than 200 microns mercury column and at a temperature of about 1470 C. for 3 hours. After cooling, the alloy in vacuum, it was annealed at about 870 C. in a protective atmosphere consisting of about 93% nitrogen and 7% hydrogen. The annealed structure had a hardness of approximately 40 Rockwell C and could then be turned on a lathe to the desired shape utilizing a steel cutting grade of tungsten carbide. Usual tolerances for grinding after hardening were permitted. The machined slug was hardened by austenitizing at about 980 C. and quenching into an oil bath. The slug was then tempered for one hour at about 200 C. Its hardness was then approximately 70 Rockwell C and after grinding and finishing, an extrusion nib of this alloy proved excellent insofar as resistance to erosion and galling were concerned.

The invention provides a high titanium, high carbon ferrous alloy which in the form of bar stock, rounds, squares, blocks, ingots and other shapes can be utilized in the fabrication of cutting tools, blanking dies, forming dies, drawing dies, rolls, hot extrusion dies, forging dies, upsetting dies, broaching tools, and in general all types of wear and/or heat resisting elements, tools or machine parts.

Although the present invention has been described in conjunction with preferred embodiments, it is to be understood that modifications and variations may be resorted to without departing from the spirit and scope of the invention, as those skilled in the art will readily understand. Such modifications and variations are considered to be within the purview and scope of the invention and appended claims.

We claim:

1. A heat treatable, high titanium, high carbon ferrous alloy comprising at least about 10% by weight titanium substantially all combined as a titanium-base carbide phase distributed substantially uniformly through a ferrous matrix containing iron as the major alloying constituent and containing combined carbon, said matrix characterized by a microstructure comprising an austenitic decomposition product.

2. A heat treatable, high titanium, high carbon ferrous alloy comprising about 10% to 70% by weight titanium substantially all combined as a titanium-base carbide phase distributed substantially uniformly through a ferrous matrix containing iron as a major alloying element and also containing combined carbon, said matrix being characterized by a microstructure comprising any one of the austenitic decomposition products pearlite, bainite and marten'site.

3. A heat treatable, ferrous alloy as in claim 2, wherein the titanium content comprises about 2.0% to 58% by stantially all combined as a titanium-base carbide phase distributed substantially uniformly through a soft ferrous matrix containing iron as a major alloying element and also containing combined carbon, said matrix being characterized by a structure of pearlite.

6. The ferrous alloy as in claim 5, wherein the titanium content comprises about 20% to 58% by weight of the alloy substantially all combined as a titanium-base carbide phase. v

7. A hardened, wear resistant, high titanium, high carbon ferrous alloy comprising at least about 10% by weight titanium substantially all combined as a titaniumbase carbide phase distributed substantially uniformly through a ferrous matrix containing iron as a major alloying element, said matrix being characterized by a microstructurc comprising martensite.

8. A hardened, wear resistant, high titanium, high carbon ferrous alloy comprising about 10% to 70% by weight titanium substantially all combined as a titaniumbase carbide phase distributed substantially uniformly through a ferrous matrix containing iron as a major alloying element, said matrix being characterized by a microstructure comprising martensite.

9. A hardened, wear resistant, ferrous alloy as in claim 8, wherein the titanium content comprises about 20% to 58% by weight of the alloy substantially all combined as a titanium-base carbide phase.

10. A hardened, wear resistant, high titanium, high carbon ferrous alloy comprising at least about 10% by weight titanium substantially all combined as a titaniumbase carbide phase distributed substantially uniformly through a ferrious matrix containing iron as a major alloying element, said matrix being characterized by a microstructure comprising bainite.

11. A hardened, wear resistant, high titanium, high carbon ferrous alloy comprising about 10% to 70% by weight titanium substantially all combined as a titaniumbase carbide phase distributed substantially uniformly through a ferrous matrix containing iron as a major alloying element, said matrix being characterized by a microstructure comprising bainite.

12. A hardened, wear resistant, ferrous alloy as in claim 11, wherein the titanium content comprises about 20% to 58% by weight of the alloy substantially all combined as a titanium-base carbide phase.

13. As an article of manufacture, heat treatable bar stock of a high titanium, high carbon ferrous alloy comprising about 10% to 70% by weight titanium substantially all combined as a titanium-base carbide phase distributed substantially uniformly through a ferrous matrix containing iron as a major alloying element and also containing combined carbon, said matrix being characterized by a microstructure comprising any one of the austenitic decomposition products pearlite, bainite and martensite.

14. The heat treatable bar stock of claim 13, wherein the alloy composition comprises 20% to 58% by weight titanium substantially all combined as titanium-base carbide phase.

References Cited in the file of this patent UNITED STATES PATENTS 2,367,358 Kott et a1. Ian. 16, 1945 FOREIGN PATENTS 710,101 Great Britain Ian. 6, 1954 OTHER REFERENCES Journal of the Electro Chemical Society, vol. 98, N0. 12, December 1951, page 469. 1 

1. A HEAT TREATABLE, HIGH TITANIUM, HIGH CARBON FERROUS ALLOY COMPRISING AT LEAST ABOUT 10% BY WEIGHT TITANIUM SUBSTANTIALLY ALL COMBINED AS A TITANIUM-BASE CARBIDE PHASE DISTRIBUTED SUBSTANTIALLY UNIFORMLY THROUGH A FERROUS MATRIX CONTAINING IRON AS THE MAJOR ALLOYING CONSITUENT AND CONTAINING COMBINED CARBON, SAID MATRIX 